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421.
Székely Eszter; Tiemeier Henning; Arends Lidia R.; Jaddoe Vincent W. V.; Hofman Albert; Verhulst Frank C.; Herba Catherine M. 《Canadian Metallurgical Quarterly》2011,11(2):425
Very few large-scale studies have focused on emotional facial expression recognition (FER) in 3-year-olds, an age of rapid social and language development. We studied FER in 808 healthy 3-year-olds using verbal and nonverbal computerized tasks for four basic emotions (happiness, sadness, anger, and fear). Three-year-olds showed differential performance on the verbal and nonverbal FER tasks, especially with respect to fear. That is to say, fear was one of the most accurately recognized facial expressions as matched nonverbally and the least accurately recognized facial expression as labeled verbally. Sex did not influence emotion-matching nor emotion-labeling performance after adjusting for basic matching or labeling ability. Three-year-olds made systematic errors in emotion-labeling. Namely, happy expressions were often confused with fearful expressions, whereas negative expressions were often confused with other negative expressions. Together, these findings suggest that 3-year-olds' FER skills strongly depend on task specifications. Importantly, fear was the most sensitive facial expression in this regard. Finally, in line with previous studies, we found that recognized emotion categories are initially broad, including emotions of the same valence, as reflected in the nonrandom errors of 3-year-olds. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
422.
Lidia MartínezAlicia Aguado Alberto MoralRubén Irusta 《Fuel Processing Technology》2011,92(2):221-228
In the present work, a preliminary study of the pyrolysis process of high density polyethylene (HDPE) in a fluidized bed is investigated in order to determine the influence between the fluidynamic properties of the bed reactor and the amount and composition of the gases produced. As is known, fluidized bed technology is a very interesting option to apply in the pyrolysis field due to i) the lack of moving parts in the hot region that facilitates the maintenance of equipment, ii) the high surface area to volume ratio available in the bed, and iii) the high heat transfer coefficient reached which governs the reaction products. But, heat and mass transfer coefficients are strongly affected by the fluidynamic properties of the bed.During the pyrolysis of HDPE, a fluidynamic characterization of the bed particles that consist of char-coated sand of HDPE has been carried out. Parameters such as the minimum fluidizing velocity (umf), terminal velocity (ut), bed height (hf), bed voidage (εf), fraction of the bed occupied by bubbles (δ), bubble diameter (db), bubble velocity (ub), the mass transfer coefficients between the bubble and the cloud (Kbc) and between the cloud and the emulsion (Kce) were determined. Subsequently, the influence of major operating variables and the fluidynamic parameters on the composition and the gas yield of the pyrolysis of HDPE were studied. 相似文献
423.
BACKGROUND: Sustained elevated blood glucose and insulin levels are linked to many health problems that may be prevented or better managed by controlling glucose availability for uptake. Glucose release from consumed starch may be altered by the processing conditions, particle size and structural features of the food, and by the addition of dietary fibres. Many approaches to lower glucose release are not suitable for all high carbohydrate foods, especially bakery products. Methods to modulate the starch digestion without compromising product quality are required. This study describes an approach to protect the granules and alter the particle size of the starch component using an extract from barley (BE). Wheat starch was suspended in the BE at different ratios and cast dried, milled to 2–3 mm particles, or finely ground to produce different particle sizes. RESULTS: The BE treatments resulted in the formation of clusters of starch granules embedded in a matrix of fibres and protein. The rate of in vitro starch digestion was decreased, and further reduction occurred when the particle size of the starch material increased. CONCLUSION: The extract provided a physical barrier that limited the starch exposure to the digestion enzymes and water that led to reduction in starch digestion and the release of glucose Copyright © 2011 Society of Chemical Industry 相似文献
424.
Diesel bus emissions measured in a tunnel study 总被引:1,自引:0,他引:1
The emission factors of a bus fleet consisting of approximately 300 diesel-powered buses were measured in a tunnel study under well-controlled conditions during a 2-d monitoring campaign in Brisbane. Particle number and mass concentration levels of submicrometer particles and PM2.5 were monitored by SMPS and DustTrak instruments at the tunnel's entrance and exit, respectively. Correlation between DustTrak and TEOM response to diesel emissions was assessed, and the DustTrak results were recalculated into TEOM equivalent data. The mean value of the number and mass emission factors was (3.11+/-2.41) x 10(14) particles km(-1) for submicrometer particles and 583+/-451 mg km(-1) for PM2.5 (DustTrak), respectively. TEOM PM2.5 equivalent emission factor was 267+/-207 mg km(-1). The results are in good agreement with the emission factors determined from steady-state dynamometer testing of 12 buses from the same Brisbane City bus fleet. The results indicate that when carefully designed, both approaches, the dynamometer and on-road studies, can provide comparable results, applicable for the assessment of the effect of traffic emissions on airborne particle pollution. A brief overview of emission factors determined from other on-road and dynamometer studies reported in the literature as well as with the regulatory values used for the vehicle emission inventory assessment is presented and compared with the results obtained in this study. 相似文献
425.
Lidia Gurau Nadir Ayrilmis Jan Thore Benthien Martin Ohlmeyer Manja Kitek Kuzman Sergiu Racasan 《Holz als Roh- und Werkstoff》2017,75(3):335-346
Surface quality of medium density fiberboard (MDF), as a very important criterion for further finishing and utilization, was evaluated using a wide range of measuring parameters (instruments, filters, filtering cut-off length, measuring length, measuring resolution, roughness parameters). However, these various approaches make any data comparison rather difficult. Furthermore, filtering the measured data with a simple Gaussian filter has proved unreliable for wood surfaces. A new, more robust approach by using a Robust Gaussian Regression filter together with a previously tested set of measuring and evaluating parameters was used in this paper in order to quantify the surface roughness of MDF manufactured from different species (beech, poplar, birch, Scots pine, mixture 50 % Scots pine and 50 % beech) and using three different grinding disc distances (0.06, 0.15 and 0.6 mm). If manufacturing parameters are kept constant, the processing roughness of MDF is similar, but variable species anatomy and fuzziness effects will give differentiation in total roughness. The results indicated that fibers made of a mixture of wood chips from Scots pine and beech led to the smoothest MDF surface, followed closely by poplar, birch, and Scots pine. The roughest surface was measured for the panels made of beech fibers. Investigating the influence of the grinding disc distance, the roughest MDF surface was obtained when a grinding gap of 0.6 mm was used. However, surface roughness was found to be quite similar applying a grinding disc distance of 0.06 mm slightly lower for 0.15 mm. This finding indicates that a too fine grinding gap does not improve the MDF surface roughness. 相似文献
426.
Estrada CS Velázquez Ldel C Escudero ME Favier GI Lazarte V de Guzmán AM 《Food microbiology》2011,28(1):21-28
The characterization of phenotypic and genotypic virulence markers of Yersinia enterocolitica strains belonging to biotypes (B) 1A, 2 and 3, mostly isolated from food in San Luis, Argentina, and the assessment of their genotypic diversity using PFGE and PCR ribotyping, were performed in our laboratory for the first time. Thirty five Y. enterocolitica strains, two reference strains and 33 strains isolated in our laboratory were studied. The presence of virF, ail, ystA, and myfA genes was investigated by multiplex PCR. The pathogenic potential of B1A strains, the most predominant biotype of Y. enterocolitica strains isolated from meat in our region, was investigated by simple PCR. Four B1A strains were positive for ystB gene. Four Y. enterocolitica 2/O:9 (bio/serotype) and two 3/O:5 strains isolated in our laboratory showed virulence-related results in the phenotypic tests and multiplex PCR. A good correlation between the expression of virulence markers and their corresponding genotypes was observed for most strains. Sixteen genomic types (GT) and 9 different intergenic spacer region (SR) groups were generated by PFGE and PCR ribotyping, respectively. In both cases the Y. enterocolitica 2/O:9 strains were separately clustered from 1A and 3/O:5 strains. Meat foods might be vehicles of transmission of pathogenic Y. enterocolitica strains in our region. 相似文献
427.
Lidia Zuccarello Catarina Barbosa Edilson Galdino Nikola Lon
ar Clia M. Silveira Marco W. Fraaije Smilja Todorovic 《International journal of molecular sciences》2021,22(15)
Immobilised dye-decolorizing peroxidases (DyPs) are promising biocatalysts for the development of biotechnological devices such as biosensors for the detection of H2O2. To this end, these enzymes have to preserve native, solution properties upon immobilisation on the electrode surface. In this work, DyPs from Cellulomonas bogoriensis (CboDyP), Streptomyces coelicolor (ScoDyP) and Thermobifida fusca (TfuDyP) are immobilised on biocompatible silver electrodes functionalized with alkanethiols. Their structural, redox and catalytic properties upon immobilisation are evaluated by surface-enhanced resonance Raman (SERR) spectroelectrochemistry and cyclic voltammetry. Among the studied electrode/DyP constructs, only CboDyP shows preserved native structure upon attachment to the electrode. However, a comparison of the redox potentials of the enzyme in solution and immobilised states reveals a large discrepancy, and the enzyme shows no electrocatalytic activity in the presence of H2O2. While some immobilised DyPs outperform existing peroxidase-based biosensors, others fail to fulfil the essential requirements that guarantee their applicability in the immobilised state. The capacity of SERR spectroelectrochemistry for fast screening of the performance of immobilised heme enzymes places it in the front-line of experimental approaches that can advance the search for promising DyP candidates. 相似文献
428.
Génesis Karendash González‐Quijano Lidia Dorantes‐Alvarez Humberto Hernández‐Sánchez María Eugenia Jaramillo‐Flores María de Jesús Perea‐Flores Arturo Vera‐Ponce de León César Hernández‐Rodríguez 《Journal of food science》2014,79(8):M1545-M1553
The microbiota associated with spontaneous fermentation of vegetables in a saline substrate may represent an important group of bacteria in the food industry. In this work, the lactic acid bacteria (LAB) Weissella cibaria, Lactobacillus plantarum, Lactobacillus paraplantarum, and Leuconostoc citreum were identified by partial 16S rRNA gene sequence analysis. In addition, entophytic bacteria such as Pantoea eucalypti, Pantoea anthophila, Enterobacter cowanii, and Enterobacter asburiae were detected, but they were irrelevant for the fermentation process and were inhibited after 12 h of fermentation when the pH decreased from 6.5 to 4.9. Moreover, 2 species of yeast were isolated and identified as Hanseniaspora pseudoguilliermondii and Kodamaea ohmeri by their partial 26S rRNA gene sequence. The growth of LAB was evaluated at different sodium chloride contents. L. citreum was the most halotolerant species followed by L. plantarum and W. cibaria with a concentration index to obtain a 50% population reduction (IC50) of 7.2%, 6.6%, and 5.2%, respectively. Furthermore, the growth of LAB and Escherichia coli O157:H7 was evaluated in the presence of the main phenylpropanoids from chilli peppers such as p‐coumaric and ferulic acid. It was determined that LAB can grow in both acids at 4 mM, unlike E. coli O157:H7, whose growth is inhibited in the presence of these acids. 相似文献
429.
Hargreaves M Parappukkaran S Morawska L Hitchins J He C Gilbert D 《The Science of the total environment》2003,312(1-3):89-101
Indoor air contains a complex mixture of bioaerosols such as fungi, bacteria and allergens, as well as non-biological particles including products from various combustion processes. To date little work has been done to investigate the interactions and associations between particles of biological and non-biological origin, however, any occurring interactions could affect pollutant behaviour in the air and ultimately the effect they have on health. The aim of this work was to examine associations between the concentration levels of airborne particles and fungi measured in 14 residential suburban houses in Brisbane. The most frequently isolated fungal genus was Cladosporium, Curvularia, Alternaria, Fusarium and Penicillium. The average outdoor and indoor (living room) concentrations of fungal colony forming units were 1133+/-759 and 810+/-389, respectively. Average outdoor and indoor (normal ventilation) concentrations of submicrometre and supermicrometre particles were 23.8 x 10(3) and 21.7 x 10(3) (particles/cm(3)), 1.78 and 1.74 (particles/cm(3)), respectively. The study showed that no statistically significant associations between the fungal spore and submicrometre particle concentrations or PM(2.5) were present, while a weak but statistically significant relationship was found between fungal and supermicrometre particle concentrations (for the outdoors R(2)=0.4, P=0.03 and for a living room R(2)=0.3, P=0.04). A similarity in behaviour between the submicrometre particle and fungal spore concentrations was that the fungal spore concentrations were related directly to the distance from the source (a nearby park), in a very similar way in which the submicrometre particles originating from vehicle emissions from a road, were dependent on the distance to the road. In the immediate proximity to the park, fungal concentrations rose up to approximately 3100 CFU/m(3), whereas for houses more than 150 m away from the park the concentrations of fungi were below 1000 CFU/m(3). Recommendations have been provided as the future study designs to gain a deeper insight into the relationships between biological and non-biological particles. 相似文献
430.
Nicoleta Bogatu Lidia Benea Elena Roxana Axente Jean Pierre Celis 《International journal of molecular sciences》2022,23(11)
This paper presents novel results on the effects of the dispersion of titanium carbide nanoparticles (50 nm mean diameter) into a nickel-plating electrolyte on the corrosion behavior of the nanocomposite layers obtained. The Ni/nano-TiC layers are compared with pure nickel layers obtained at the same electrodeposition parameters with 60 mA·cm−2 current density and 10 min deposition time. The comparative corrosion performances are investigated using a three-electrode electrochemical cell in a solution (mixed boric acid with lithium hydroxide), which simulates the primary water circuit of pressurized water reactors (PWRs). Open circuit potential measurement and electrochemical impedance spectroscopy were employed as the electrochemical methods, using an electrochemical workstation connected to an electrochemical cell, as well as a PC with software to drive the experimental work. The results clearly revealed enhanced corrosion properties for the Ni/nano-TiC hybrid layers as compared to the pure Ni layers. The significantly improved corrosion behavior can be attributed to the TiC nanoparticles embedded into the Ni matrix, which have the effect of insulating centers at the composite layer/corrosive solution interface. 相似文献